"We'll see where he's at when we come back to work Wednesday," Allen said. "It's more of a relation to the surgery that he had this offseason as opposed to the heart condition."

Hayden was rushed into surgery last November for a tear of the inferior vena cava, the large vein that carries blood from the lower half of the body to the heart, after a collision in practice. Doctors had to cut through Hayden's sternum to save him. The injury is 95 percent fatal.

The 23-year-old had his offseason cut short when he underwent surgery in late May to remove scar tissue from his abdominal region.

Hayden wasn't available after practice and players were excused from evening meetings. They do not have to check back in until an 11 p.m. curfew on Tuesday. "We'll kind of re-evaluate (Hayden) after that," Allen said.

The 12th overall pick in this year's draft, Hayden has practiced every day but has been wearing a red jersey normally reserved for quarterbacks and kickers because he has not been cleared for contact yet.

During a team scrimmage, Hayden collided with a wide receiver in the end zone then jogged off the field. He pulled up later in practice during a drill pairing cornerbacks against receivers and clutched at his leg. Although he returned to finish the workout, the Raiders are still being cautious with their first-rounder. Allen said Hayden would not have played against Dallas regardless of what happened in practice.